Apparatus for perforating film from rolls



July 14, 1964 D. M. HULETT APPARATUS FOR PERFORATING FILM FROM ROLLS Filed Feb. 23, 1962 3 Sheets-Sheet 1 6 3 AW l -2 I f r p. a 5 3 "a 22 07/ O 7 .H M m M a l q 9 v E o 4 3 6 w n 1 WT 1 m4 w 8 w. e l- 3 0 I13 4 m. 6 2 8 8) I r1 6 8 m 3 I -iiw I 7 O 7 6 w 8 5 v, W 1 n a A. 6 4 2 o O O 6 29 I (16 3 A (i4 0 n F 3 A Mn. HQIQI H n h I u 5 l 4 4 O 6 O IIMI|I llll ll q 3 M Q "W 8 F 2 I I INVENTOR. AOJVALA M 1/1/1577 wa /M JTTOR/VEYS July 14, 1964 D. M. HULETT 3,140,838

APPARATUS FOR PERFORATING FILM FROM ROLLS Filed Feb. 23, 1962 3 Sheets-Sheet 2 INVEN TOR. Anna M l/uzzrr WM OZQ/ ATTORNEYS July 14, 1964 D. M. HULETT APPARATUS FOR PERFORATING FILM FROM ROLLS 3 Sheets-Sheet 5 Filed Feb. 23, 1962 m N M T T A United States Patent 3,149,833 APPARATUS FOR PERFORATENG FILM FRQM ROLLS Dcnald M. Hulett, Independence, Mu, assignor to Clark Products, Inc, Chicago, 1th, a corporation of Ohio Filed Feb. 23, 1962, Ser. No. 174,973 8 Claims. (Cl. 242-56) This invention relates to an apparatus for perforating thin webs of material such as plastic film, paper, and the like, and more particularly to the formation of a multiplicity of relatively small openings or slots in a linear series substantially transversely of the direction of travel of a moving web. The invention is particularly adapted to form perforations in a plurality of spaced linear series on a web to provide lines of separation whereby portions or sheets of the web material may be separated therefrom.

The expedients heretofore commonly resorted to in forming perforations in web from rolls, as for example plastic film, have required expensive machinery wherein the web is fed between two rotating members, one having piercing members and the other a platen cooperating therewith to perforate the web therebetween. Also, with such structures, a linear series of perforations are made simultaneously which requires substantial pressure loading to effect the punching or perforating operation.

The principal objects of the present invention are to provide an' apparatus by which a plastic film or paper in the form of a web from a roll may be perforated without the disadvantage heretofore encountered; to provide an apparatus wherein a web is perforated with a linear series of small openings or slots that extend transversely of the direction of travel of the web wherein the perforations are made one after another in sequence to form the linear series; to provide such an apparatus wherein a web is removed from a roll and progressively fed through a machine and provided with spaced transverse series of perforations and then is rewound in a roll from which the web is adapted for subsequent severance into sheets of the required size; to provide such a structure wherein the perforations are formed by a perforating blade and an abrading bar with the web moving with the blade between the blade and bar with the bar at an angle to the direction of travel of the web; to provide such a perforating apparatus with web-engaging members having spaced engagement with opposed faces of the web to eliminate wrinkles therein as it is wound onto a roll; to provide such an apparatus in which the web is moved by rotation of a blade-carrying roller and driving of the rewinding roller to maintain tension on the perforated web that is less than the force required for separation thereof; and to provide an apparatus for perforating a web such as a plastic film from a roller that is economical to manufacture, easily maintained and efficient in operation.

Other objects and advantages of this invention will become apparent from the following description taken in connection with the accompanying drawings wherein are set forth by way of illustration and example certain embodiments of this invention.

FIG. 1 is a plan view of a web-perforating apparatus with portions broken away to illustrate drive members therefor.

FIG. 2 is a vertical sectional view through the perforating apparatus taken on the line 2-2, FIG. 1.

FIG. 3 is a vertical sectional view taken through the apparatus on the line 33, FIG. 1.

FIG. 4 is a partial perspective view showing the relationship of the abutment bar and blade-carrying roller.

FIG. 5 is an enlarged partial perspective view of the blade-carrying roller and the abutment bar and mounting therefor.

FIG. 6 is a longitudinal sectional view through the Web-rewinding roller and mounting.

FIG. 7 is a partial perspective view of the abutment member.

Referring more in detail to the drawings:

1 generally designates a perforating apparatus adapted to have a supply roll 2 containing a substantial quantity of unperforated plastic film or paper 3 in the form of a continuous unperforated web. The apparatus is particularly adapted for perforating thin plastic film such as is used for wrapping of packages and the like by providing a linear series of perforations transversely of the web with one series of perforations 4 spaced from another series 5 longitudinally of the web to form lines of separation defining sheets 6 therebetween that are separable from the web.

The web or film is drawn from the supply on the roll 2 and is then guided by a roller 7 to and around a rotative carrier or roll 8 carrying a perforating blade 9. When the traveling web passes about the roll 8, it moves between the surface 10 of said roll and a substantially stationary blade-cooperating abutment member 11 to form perforations in the web at intervals therein as the blade passes under said abutment member. The web moves from roll 8 over a stationary guide 12 and under a second guide 13 and is then guided by a guide roller 14 to a rotative mandrel 15 which is also driven to rewind the perforated web. The blade 9 extends substantially transversely of the path of travel of the web, and the abutment bar 11 is arranged diagonally of said path or at an acute angle thereto whereby the contact of the web between the blade and abutment bar is substantially a point contact with said point of contact moving across the web as the blade moves under the abutment in the direction of travel of the web.

In the structure illustrated, the apparatus 1 includes a frame 16 mounted on suitable support such as legs 17 whereby the frame is substantially horizontally disposed. The frame preferably is formed of spaced side members 18 and 19 having their ends connected by members 26 and 21, said side members also preferably being connected by an intermediate member 22, all secured together to form a rigid structure, the spacing between the members 20 and 22 being substantially greater than the width of a web to be perforated. Bearing members 23 and 24 are preferably mounted on the frame members 20 and 22 adjacent the side member 19 to rotatably mount the supply roll 2. It is preferred that the supply roll include a tubular member 25 on which the supply of the web is suitably mounted or rolled. The tubular member has end portions adapted to receive frusto-conical members 26 and 27 to support same with the member 26 fixed on a shaft 28 that is rotatably mounted in the hearing member 24 and held against end movement relative thereto by suitable collars 29. The other frusto-conical member 27 is carried on a shaft 30 that is slidable and rotatable in the bearing member 23 with a spring 31 between the member 27 and the bearing member 23 to urge the frusto-conical end toward the adjacent end of the member 25 to maintain engagement therewith whereby said tubular member is rotatably mounted and removably carried by the shafts 28 and 30 in the bearing members 24 and 23 respectively. This provides a mounting wherein the supply is rotatably in response to pulling of the web therefrom.

The frame members 20 and 22 have upstanding portions 32 and 33 respectively extending from adjacent the bearing members 23 and 24 to the side member 18, said upstanding portions having upper faces 34 on which are I tatably mounted relative thereto.

mounted bearing members 35 and 36 adjacent the side member 18 for supporting shaft members to removably carry a mandrel 37 on which the web is rewound above the side member 18, as later described. Plate members 38 and 39 are secured to and upstand from the portions of the frame members 32 and 33 respectively that are adjacent the bearings 23 and 24 with said plate members being adapted to. rotatably mount a shaft 40 that carries the blade carrier or roll 8, preferably at an elevation above the axis of the shafts 28 and 30, as illustrated in FIG. 2.

The guide roller 7 has a shaft 41 mounted in free ends of arms 42 whereby the roller 7 is rotatable relative thereto. The other ends of the arms 42 are pivotally mounted on bearing members 43 carried by the frame members 32 and 33 and said arms are biased by springs 44 to urge the guide roller 7 toward the roller 8, the guide roller preferably being positioned whereby the web moves therearound and has engagement with a substantial arc of the surface of the blade carrier or roller 8 to form a frictional engagement and driving of the roller 8 will pull the web from the supply roller 2.

The guide roller 14 has a shaft 45 mounted in free ends of the arms 46 whereby the guide roller 14 is ro- The other ends of the arms 46 are pivotally mounted as by pins 47 on the plate members 38 and 3? whereby the arms 46 tend to swing downwardly and move the guide roller 14 therewith through gravity. The axis of the guide roller 14 is preferably substantially vertically relative to the axis of the mandrel 37. A stationary guide member 12 is fixed relative to the frame members 32 and 33 and extends transversely of the path of travel of the web with a rounded surface 48 engaging said web. In the illustrated structure, the guide member 12 is a rod that is cylindrical in cross-section with a straight portion 49 adapted to engage the under side of the web between the guide roller 14 and the knife-carrying roller 8. The guide 12 has depending leg members 50 extending downwardly between the arms 46 with lower ends fixed as at 51 in the frame members 32 and 33. In the structure illustrated, the web moves from the knife-carrying roller 8 over the portion 49 of the guide 12 and then under a guide member 13 and over the guide roller 14. The guide member 13 has a rounded surface engaging the web and, in the illustrated structure, is in the form of a rod with a cross portion 52 with depending legs 53 that terminate in portions 54 that are secured to the arms 46 whereby said guides 13 are held at a fixed relationship to the guide roller 14.

In the mounting of the mandrel 37, a drive shaft 55 is rotatably mounted in the bearing 36 and an axially aligned bearing member 56 that is carried on a plate 57 secured to the side members 18 and 19 between the members 22 and 21, as illustrated in FIG. 1. The drive shaft 55 extends from the bearing 36 and has fixed thereon a frusto-conical end 58 adapted to be engaged in the end of the mandrel 37. The other end of the mandrel is removably engaged with the frusto-conical member 59 fixed on a shaft 60 that is rotatably and slidably mounted in the bearing member 35, a spring 61 being sleeved on the shaft 60 with ends engaging the bearing member 35 and the frusto-conical member 59 to urge said frustoconical member into engagement with the mandrel and cooperate with the member 58 in removably supporting said mandrel for rotation in response to drive of the shaft 55 and wind the web thereon, the web being held in contact as it is wound by the guide roller 14 over which the web passes to the mandrel, as illustrated in FIG. 2.

has a pulley 67 fixed thereto over which operates a belt 68 having driving engagement with a pulley 69 fixed on a countershaft 7t) rotatably mounted in bearing members 71 that are carried by the plate 57. A clutch member 72 on the countershaft 78 is actuated through a control rod 73 to selectively provide driving engagement with a pulley 74 loosely mounted on said shaft 78 with a belt 75 operatively connecting the pulley 74 with a driven pulley 76 that is fixed on the shaft 40 to thereby drive the blade carrier roller 8. The motor shaft 63 also has a pulley 77 fixed thereon which is operatively connected by a belt 78 to a fluid clutch or coupling 79 which, through fluid therein, drives the shaft 55. A Wheel 80 is fixed to the shaft 55 and may be grasped to stop the rotation of said shaft 55, as the fluid coupling or clutch structure 79 is a conventional type which provides a drive through the fluid but will have differential movement or slippage when more than a predetermined resistance to rotation is applied to the member driven thereby. The fluid coupling or clutch is so regulated that slippage occurs at a resistance that is less than the tension on the web that would tend to separate same at the perforation lines 4 or 5. The drive of the shaft 55 is such that the peripheral speed at which the mandrel 37 tends to be rotated is slightly greater than the peripheral speed of the blade carrier roller 8 with some slippage of the fluid coupling 79 so as to always maintain a tension on the web as it moves over the various rollers in its path, as illustrated in FIG. 2. During such movement, the guide rollers 7 and 14 and also the guides 12 and 13 tend to maintain the web, as for example a thin film of plastic, stretched flat to eliminate any wrinkles or the like that might occur from the tension placed on the web as it is moved through the machine.

The perforating of the thin plastic film or web, as it is moved through the machine between the supply roll and the rewinding or other use of the perforated film, is effected through a cooperation between the blade 9 and the abutment bar 11. The abutment member or bar is positioned whereby it is at an angle to the blade 9 and has a face 81 that extends across and has substantially uniform close spacing to the surface 18 of the roller 8 and, therefore, is curved to conform to the surface or form a slight spiral relative thereto. In the structure illustrated, the abutment member 11 is in the form of a rod having ends 82 fixed relative to the bearing plates 38 and 39, said rod preferably being generally cylindrical in cross-section and slightly bendable in order to conform to the curvature and lie close to the surface of the cylindrical roller 8. The rod being bendable is capable of more flexing in the center portion and, therefore, it is preferred that the projection of the blade 9 be less adjacent the ends of the roller 8 than at the center to provide a slight arcuate contour so that the engagement of said blade with the abutment bar in the perforating of the web accommodates the resiliency of the bar to form substantially uniform perforations across the width of the web. While slight flexing of the rod is desirable, it is also desired that it be limited and that the flexing is controlled so that it is only away from the face of the cylinder. This control of the flexing is provided by a rigid plate member 33 having ends slidable in ways 84 of brackets 85 secured to the adjacent faces of the plates 38 and 39, the ways being arranged whereby the plates is adjustable generally radially outwardly from the cylinder. The brackets 85 have adjusting screws 86 engaging the edges 87 of the plate to effect the adjustment in the ways 84. The plate has rigid guide portions 88 secured thereto in opposed relation to slide blocks 89 spaced therefrom by a rigid rail 90, the blocks 89, rail 98 and portions 88 being secured together by suitable fastening devices such as bolts 91 to maintain adjacent faces 92 and 93 of the blocks 89 and portions 88 in parallel planes. Slidably mounted between the faces 92 and 93 is a cylindrical substantially rigid backing bar 94 positioned above the rod of the abutment member with a cushion member 95 interposed therebetween. The cushion preferably is an elongate strip of sponge rubber or the like. A plurality of adjusting screws 96 are arranged in the rail 90 and have ends engaged with the backing bar 94 to hold same against the cushion 95 with a predetermined pressure that is varied by curving of the member 94 by the screws 96 so that the abutment member rod is permitted a controlled flexing as it is engaged by teeth 97 of the blade 9 in the perforating of the web passing therebetween. The sharpened edge of the blade preferably has notches 93 spaced along the length thereof to provide the spaced teeth 97 which, in the illustrated structure, are elongated whereby the perforations are small slits. It is preferred that the face 81 of the abutment member be rounded whereby the contact of the teeth relative thereto is substantially along a line of the face 81. Also, it is preferred that said face 81 have minute ridges 99 extending longitudinally thereof to form an abrading surface that cooperates with the points in the blade to form the perforations in the web.

In using an apparatus constructed as described, a supply of thin plastic film or other web to be perforated is in the form of a roll and is placed on a tubular member and then the shaft 30 is drawn outwardly to provide a spacing between the frusto-conical portions 26 and 27 whereby the tube can be inserted therebetween. Then the shaft 30 is released whereby the spring 31 will urge the frusto-conical member 27 inwardly to support the tube or roll for rotation in the machine. The web is then pulled from the supply roll and passed under the guide roll 7 and is then inserted between the surface of the roll 8 and the abutment member 11. The web is then drawn therethrough and passed over the guide member 12 under the guide member 13 and over the guide roller 14. A roll mandrel 37 to receive the perforated web is supported on the frusto-conical members 58 and 59 and the lead end of the web is secured to said mandrel. Then the motor 62 is energized to drive the shaft 55 through the fluid clutch 79. The clutch 72 is actuated to also provide a drive through the shaft 40 to the roll 8. The fluid clutch 79 permits slippage whereby the mandrel 37 to rotated to maintain a tension on the web, and the engagement of the web with the surface of the roll 8 also provides a driving engagement therewith to aid in drawing the web from the supply roll. On each revolution of the roll 8, the teeth of the blade 9 engage the under surface of the web and, as the blade moves under the abutment member, the teeth on the blade at one end thereof press into the web at the point where the web is engaged on opposite sides by the blade teeth and the abutment member. As the web moves at the same peripheral speed as the roll 3, the opposed engagement point of the blade and abutment member with the film moves across the web, providing a progressive perforation to form a series of the perforations extending across the web. The blade being transversely of the path of travel of the web causes the series of perforations to be linear and also transversely of the web. Also, when there is one blade in the roll 8, the circumference of the roll provides the spacing between the linear series of perforations to define the length of the sheets that can be separated from the web along the perforations. The fluid coupling is such that substantially constant tension is applied to the web, said tension being less than the force required for separation of the web along the lines of perforation. Also, this tension holds the web in engagement with the guides 12 and 13 whereby they tend to keep the web flat and avoid any tension wrinkles therein. As the web is wound onto the mandrel 37, the guide roller 14 will rise as the web builds up on the mandrel, it being held onto the web as it is wound by gravity. During such movement of the roller 14, the relationship thereof with the guide member 13 is maintained to provide cooperation between the surfaces thereof engaging the web to prevent wrinkles therein. After a roll of a web is perforated, the mandrel 37, which may be a tubular center for the perforated roll for use in shipping, is removed by withdrawing the conical member 59 therefrom and another mandrel is placed between the frusto-conical members 58 and 59 so that it is in driving engagement relative to the shaft 55. Then, another supply roll of web is placed in rotary position and supported on the shafts 2'7 and 2d and the web again started through the machine for perforating same.

It is to be understood that while I have illustrated and described one form of my invention, it is not to be limited to the specific form or arrangement of parts herein described and shown except insofar as such limitations are included in the claims.

What I claim and desire to secure by Letters Patent is:

1. Apparatus for forming a linear series of perforations transversely of a moving web to define lines of separation in said web comprising,

(a) a blade carrier extending transversely of the path of travel of said web,

(1)) a blade mounted on said carrier and having a cutting edge adapted to engage the web in response to movement of the carrier,

(c) an elongate abutment member extending across the path of the travel of the web and substantially equally spaced radially from the carrier with an adjacent surface adapted to be engaged by portions of the cutting edge of the blade as the blade is moved thereby whereby the cutting edge of the blade and abutment member cooperate in perforating a web passing therebetween,

(0?) means supporting ends of said elongate abutment member, said abutment member being bendable between said supporting means in response to force applied to the abutment member by the portion of the blade engaged therewith as the blade passes thereunder,

(e) and a rigid backing bar supported adjacent the abutment member and adjustable relative thereto to limit the bending of the abutment bar.

2. Apparatus for forming a linear series of perforations transversely of a moving web to define lines of separation of sheets from said web comprising,

(a) a rotatable blade carrier having its axis transversely of the path of travel of said web,

(b) a blade mounted on said carrier and having a serrated cutting edge adapted to engage the web at intervals in response to rotation of the carrier,

(0) an elongate abutment member extending across the path of the travel of the web and substantially equally spaced radially from the axis of the carrier with an adjacent surface adapted to be engaged by portions of the serrated cutting edge of the blade as the blade is moved thereby whereby the cutting edge of the blade and abutment member cooperate in perforating a web passing therebetween,

(d) means supporting ends of said elongate abutment member, said abutment member being bendable between said supporting means in response to force applied to the abutment member by the portion of the blade engaged therewith as the blade passes thereunder,

(e) a rigid backing bar supported adjacent the abutment member and adjustable relative thereto to limit the bending of the abutment bar,

(f) and a resilient cushion member between the abutment member and the rigid backing bar.

3. Apparatus as set forth in claim 2 wherein:

(a) the adjacent surface of the abutment member has a plurality of minute ridges extending longitudinally thereof.

4. Apparatus for forming a linear series of perf0rations transversely of a moving web to define lines of separation of sheets from said web comprising,

(a) a rotatable blade carrier having its axis transversely of the path of travel of said web,

also,

(b) a blade mounted on said carrier and having a ser rated cutting edge extending outwardly from said carrier surface,

() a stationary elongate abutment member arranged (c) a stationary elongate abutment member arranged substantially diagonally relative to the path of travel of the web and in overlying relation to the carrier,

frame with its axis transversely of the path of travel of said web and between the supply roller and the winding roller, said carrier having a cylindrical webengaging surface,

substantially diagonally relative to the path of travel (e) a blade mounted on said carrier and having a of the web and in overlying relation to the carrier, serrated cutting edge extending outwardly from said said abutment member having a surface adjacent said carrier surface, said blade being in a radial axial carrier surface and having a substantially equal spacplane of said carrier,

ing therefrom slightly less than the extension of the (f) a stationary elongate abutment member arranged blade from said carrier surface whereby said abut- 10 substantially diagonally relative to the path of travel ment member and cutting edge of the blade cooperof the web and in overlying relation to the carrier, ate in perforating a web passing therebetween at a said abutment member having a transversely arcuate linear speed corresponding to the peripheral speed surface adjacent said carrier surface and having a of the rotating carrier, said perforations being formed substantially equal spacing therefrom slightly less at a point of engagement of the blade cutting edge than the extension of the blade from said carrier surand abutment member with the point moving proface whereby said abutment member and cutting gressively across the path of travel of the web as the edge of the blade cooperate in perforating the web blade moves under the abutment member in its angupassing therebetween at a linear speed correspondlar relation thereto, ing to the peripheral speed of the rotating carrier,

((1') said elongate abutment member having fixed ends (g) means fixing the abutment member at ends thereof and being bendable therebetween in response to force relative to said frame With said abutment member applied by the portion of the blade engaged therebeing bendable between said end portions in response with as the blade passes thereunder, to force applied by the portion of the blade engaged (e) and means adjustably mounted relative to said therewith,

abutment member to limit bending thereof. (/1) means operatively connected with the blade car- 5. Apparatus for forming a linear series of perforations rier to rotate same and move the web thereover,

transversely of a moving web to define lines of separation (i) means including a fiuid coupling operatively conof sheets from said web comprising, necting said drive means with the winding roller to (a) a rotatable blade carrier having its axis transrotate same and maintain a predetermined tension versely of the path of travel of said web and having on the web between the winding roller and said a cylindrical web-engaging surface, blade carrier,

(b) a blade mounted on said carrier and having a ser- (j) and spaced guide bars extending across the web rated cutting edge extending outwardly from said cartransversely of the path thereof and engaging oprier surface, said blade being in a radial axial plane posed surfaces of the web between the blade carrier of said carrier, and the winding roller, said guide bars cooperating to smooth tension wrinkles from the Web as it is wound on the winding roller. 7. Apparatus for forming a linear series of perforations transversely of a moving web of plastic film to define lines of separation of sheets from said film web comprising,

blade from said carrier surface whereby said abutment member and cutting edge of the blade cooperate in perforating a web passing therebetween at a linear speed corresponding to the peripheral speed (a) a frame,

(17) means on the frame adapted to rotatably and removably support a supply roll of unperforated web of plastic film,

of the rotating carrier, said perforations being formed (c) means on the frame adapted to rotatably and reat a point of engagement of the blade cutting edge movably mount a web-receiving roll member with and abutment member with the point moving prothe axis of rotation parallel with the axis of rotagressively across the path of travel of the web as the tion of the supply roll mounting means and in spaced blade moves under the abutment member in its angurelation thereto whereby the web can be moved in a lar relation thereto, path of travel from the supply roller to the winding (d) means supporting ends of said elongate abutment roller, member, said abutment member being bendable be- (d) a rotatable blade carrier rotatably mounted on the tween said supporting means in response to force frame with its axis transversely of the path of travel applied to the abutment member by the portion of of said web and between the supply roller and the the blade engaged therewith as the blade passes winding roller, said carrier having a cylindrical webthereunder, engaging surface,

(e) and a rigid backing bar supported adjacent the (e) a blade mounted on said carrier and having a abutment member and adjustable relative thereto serrated cutting edge extending outwardly from said to limit the bending of the abutment bar. carrier surface, said blade being in a radial axial 6. Apparatus for forming a linear series of perforaplane of said carrier,

tions transversley of a moving web of plastic film to de (1) a stationary elongate abutment member arranged fine lines of separation of sheets from said film web comsubstantially diagonally relative to the path of travel prising, of the web and in overlying relation to the carrier,

(a) a frame, said abutment member having a transversely arcuate (b) means on the frame adapted to rotatably and resurface adjacent said carrier surface and having a movably support a supply roll of unperforated web substantially equal spacing therefrom slightly less of plastic film, than the extension of the blade from said carrier (0) means on the frame adapted to rotatably and resurface whereby said abutment member and cutmovably mount a web-receiving roll member with ting edge of the blade cooperate in perforating the the axis of rotation parallel with the axis of rotation web passing therebetween at a linear speed corresponding to the peripheral speed of the rotating carrier,

(g) a plurality of minute ridges extending longitudinally of the abutment member on the arcuate surface thereof,

(h) means fixing the abutment member at ends thereof relative to said frame with said abutment member being bendable between said end portions in response to force by the portion of the blade engaged therewith,

(i) means resiliently and adjustably engaging and guiding said abutment member to limit bending thereof to retain the surface of the abutment member engaged with the blade cutting edge portion passing thereunder,

(j) means operatively connected with the blade carrier to rotate same and move the web thereover,

(k) means including a fluid coupling operatively connecting said drive means with the winding roller to rotate same and maintain a predetermined tension on the web between the winding roller and said blade carrier,

(1) and means extending transversely of the path of the web and frictionally engaging opposed surfaces thereof at spaced lines between the carrier and the winding roller to remove tension wrinkles from the web as it is wound on the winding roller.

8. Apparatus for forming a linear series of perfora tions transversely of a moving web of plastic film to define lines of separation of sheets from said film web comprising,

(a) a frame,

(b) means on the frame adapted to rotatably and removably support a supply roll of unperforated web of plastic film,

() means on the frame adapted to rotatably and removably mount a web-receiving roll member with the axis of rotation parallel with the axis of rotation of the supply roll mounting means and in spaced relation thereto whereby the web can be moved in a path of travel from the supply roller to the winding roller,

(d) a rotatable blade carrier rotatably mounted on the frame with its axis transversely of the path of travel of said web and between the supply roller and the winding roller, said carrier having a cylindrical web-engaging surface,

(e) a blade mounted on said carrier and having a serrated cutting edge extending outwardly from said carrier surface, said blade being in a radial axial plane of said carrier,

(f) a swingably mounted guide roller adapted to engage the web between the supply roller and said carrier and urge the web against said carrier surface,

(g) a guide roller swingably mounted on the frame and engaging the web adjacent the winding roller to hold the web thereon, spaced guide members engaging opposed surfaces of the web adjacent to and spaced from said second guide roller to cooperate therewith to smooth wrinkles from said web,

(12) a stationary elongate abutment member arranged substantially diagonally relative to the path of travel of the web and in overlying relation to the carrier, said abutment member having a transversely arcuate surface adjacent said carrier surface and having a substantially equal spacing therefrom slightly less than the extension of the blade from said carrier surface whereby said abutment member and butting edge of the blade cooperate in perforating the web passing therebetween at a linear speed corresponding to the peripheral speed of the rotating carrier,

(i) a plurality of minute ridges extending longitudinally of the abutment member on the arcuate surface thereof,

(1') means fixing the abutment member at ends thereof relative to said frame with said abutment member being bendable between said end portions,

(k) means resiliently and adjustably engaging and guiding said abutment member to limit bending thereof to retain the surface of the abutment member engaged with the blade cutting edge portion passing thereunder,

(1) means operatively connected with the blade carrier to rotate same and move the web thereover, (m) and means including a fluid coupling operatively connecting said drive means with the winding roller to rotate same and maintain a predetermined tension on the web between the winding roller and said blade carrier.

References Cited in the file of this patent UNITED STATES PATENTS 1,328,431 Hudson Jan. 20, 1920 2,592,268 Gerbe Apr. 8, 1952 2,805,715 Novick Sept. 10, 1957 2,870,840 Kwitek Jan. 27, 1959 

1. APPARATUS FOR FORMING A LINEAR SERIES OF PERFORTIONS TRANSVERSELY OF A MOVING WEB TO DEFINE LINES OF SEPARATION IN SAID WEB COMPRISING, (A) A BLADE CARRIER EXTENDING TRANSVERSELY OF THE PATH OF TRAVEL OF SAID WEB, (B) A BLADE MOUNTED ON SAID CARRIER AND HAVING A CUTTING EDGE ADAPTED TO ENGAGE THE WEB IN RESPONSE TO MOVEMENT OF THE CARRIER. (C) AN ELONGATE ABUTMENT MEMBER EXTENDING ACROSS THE PATH OF THE TRAVEL OF THE WEB AND SUBSTANTIALLY EQUALLY SPACED RADIALLY FROM THE CARRIER WITH AN ADJACENT SURFACE ADAPTED TO BE ENGAGED BY PORTIONS OF THE CUTTING EDGE OF THE BLADE AS THE BLADE IS MOVED THEREBY WHEREBY THE CUTTING EDGE OF THE BLADE AND ABUTMENT MEMBER COOPERATE IN PERFORATING A WEB PASSING THEREBETWEEN. 